It's an indictment of our fact-averse political culture that a statement of the blindingly obvious could sound so revolutionary. "Our insatiable demand for illegal drugs fuels the drug trade," Secretary of State Hillary Clinton told reporters on her plane Wednesday as she flew to Mexico for an official visit. "Our inability to prevent weapons from being illegally smuggled across the border . . . causes the deaths of police, of soldiers and civilians."

Amazingly, U.S. officials have avoided facing these facts for decades. This is not just an intellectual blind spot but a moral failure, one that has had horrific consequences for Mexico, Colombia, Peru, Bolivia and other Latin American and Caribbean nations. Clinton deserves high praise for acknowledging that the United States bears "shared responsibility" for the drug-fueled violence sweeping Mexico, which has claimed more than 7,000 lives since the beginning of 2008. But that means we will also share responsibility for the next 7,000 killings as well.

Our long-running "war on drugs," focusing on the supply side of the equation, has been an utter disaster. Domestically, we've locked up hundreds of thousands of street-level dealers, some of whom genuinely deserve to be in prison and some of whom don't. It made no difference. According to a 2007 University of Michigan study, 84 percent of high school seniors nationwide said they could obtain marijuana "fairly easily" or "very easily." The figure for amphetamines was 50 percent; for cocaine, 47 percent; for heroin, 30 percent.

At the same time, we've persisted in a Sisyphean attempt to cut off the drug supply at or near the source. When I was The Washington Post's correspondent in South America, I once took a nerve-racking helicopter ride to visit a U.S.-funded military base in the Upper Huallaga Valley of Peru. It was the place where most of the country's coca -- the plant from which cocaine is processed -- was being grown, and the valley was crawling with Maoist guerrillas who funded their insurgency with money they extorted from the coca growers and traffickers. Eventually, the coca business was eliminated in the Upper Huallaga. But now it's flourishing in other parts of Peru, and last year authorities there seized a record 30 tons of cocaine -- meaning, by rule of thumb, that at least 10 times that much was probably produced and shipped.

In Colombia, I saw how the huge, brutally violent Medellin and Cali cocaine cartels threatened to turn the country into the world's first "narco-state." The Colombian government, again with U.S. assistance, managed to pulverize these sprawling criminal organizations into smaller units, but the business continues to thrive -- and to provide most of the cocaine that finds its way to the American market. Last year, Colombian authorities seized 119 tons of cocaine. Money from the drug trade sustains the longest-running leftist insurgency in the hemisphere. Ever inventive, the Colombian traffickers have gone so far as to build their own miniature submarines to smuggle illicit cargo into the United States.

And now Mexico has become the focal point of the drug trade, with its cartels blasting their way to dominance in the business of bringing marijuana, methamphetamine, cocaine and other drugs to the American market. Violence among drug gangs, not just along the border but throughout the country, has reached crisis levels. The government's strategy is to break up the big cartels, as the Colombians did. But even if authorities succeed, the industry will live on.

In the case of Mexico, there's a complicating factor: This is a two-way problem. While drugs are being moved north across the border, powerful assault weapons -- purchased in the United States -- are being moved south to arm the cartels' foot soldiers. Clinton's statement about "shared responsibility" recognizes that if we expect Mexico to do something about the flow of drugs, we're obliged to do something about the counterflow of guns.

First, though, let's be honest with ourselves. This whole disruptive, destabilizing enterprise has one purpose, which is to supply the U.S. market with illegal drugs. As long as the demand exists, entrepreneurs will find a way to meet it. The obvious demand-side solution -- legalization -- would do more harm than good with some drugs, but maybe not with others. We need to examine all options. It's time to put everything on the table, because all we've accomplished so far is to bring the terrible violence of the drug trade ever closer to home.